In Visual Studio Code, Flutter language classes and widgets are not colored for me, but some words are blue .
The Flutter and Dart plugins are installed and flutter doctor run without any problem.
Please look at this:

In Visual Studio Code, Flutter language classes and widgets are not colored for me, but some words are blue .
The Flutter and Dart plugins are installed and flutter doctor run without any problem.
Please look at this:

Open Settings (Cmd+, on Mac), and search for theme color. You will find a Workbench: Color Theme setting. Here select Dark+ or Light+ and that should help.
Another option if you don't want to use the Dark+ or Light+ themes (as a matter of taste e.g., I personally prefer the Visual Studio Dark - C++ theme) is to add the following to your settings.json:
"editor.tokenColorCustomizations": {
"textMateRules": [
{
"scope": ["support.class.dart"],
"settings": {
"foreground": "#4EC9B0" // the C++ theme class color
}
}
]
},